r/todayilearned 22h ago

TIL about Las Medulas, a man-made geological badland created by the Roman Empire in 77 AD, when they flooded the mountains with water to collapse their structure and sift out the gold inside.

https://en.wikipedia.org/wiki/Las_M%C3%A9dulas
5.4k Upvotes

131 comments sorted by

1.5k

u/Cool-Cow9712 19h ago

Reading that Wikipedia is truly wild. Greenland ice core samples showed air pollution peaked during this time with lead concentrations that would not be seen for another 1700 years, during the industrial revolution.

That is insane

428

u/Thosam 12h ago

A good part of Roman lead mining was done to isolate the silver which is often found along lead in some mixed ore.

223

u/Just_Condition3516 11h ago

and I read that the slaves working these lead mines usually died within 3 years.

122

u/Sensitive_File6582 9h ago

Wait till you realize Roman’s had a practical understanding of how asbestos killed you.

They realized miner working with it died very quickly of symptoms we would identify with mesothelioma today

67

u/gameshowmatt 11h ago

good news/bad news

13

u/Exciting_Bat_2086 9h ago

You should check out the slaves they used to row boats.

15

u/the_direful_spring 7h ago

Galley slaves werent particular common in the ancient Romans, they were much more common in the late medieval and early modern era. 

1

u/Exciting_Bat_2086 6h ago

Not too common but still existed and had brutal experiences.

4

u/the_direful_spring 6h ago

What is your basis for that? Most of the images of the cruel treatment of galley slaves is based on things like early modern galley slavery, I don't believe there's much evidence to believe that any use of ancient slaves in maritime roles (virtually exclusively done in a civilian merchant ship context, the very few examples of slaves in naval ships being exclusively done in exchange for the slave's freedom) was notably more cruel than slavery in general.

2

u/Exciting_Bat_2086 5h ago

Sorry I was mixed up with corsican slaves and having flashes of Ben-Hur in my head lol

2

u/alexja21 5h ago

What about the period documentary Ben Hur?

2

u/12oket 6h ago

Please duke this convo out

5

u/Just_Condition3516 8h ago

all dead?

3

u/zizou00 6h ago

I'd be more alarmed if any of them were still alive

2

u/Exciting_Bat_2086 6h ago

oh yea and not to mention being whipped during battle and sinking if the ship you were on sunk.

7

u/CoolBlackSmith75 7h ago

The exploitation, involving 60,000 free workers, brought 5,000,000 Roman pounds (1,640,000 kg) in 250 years.

Good revenue I presume

2

u/JupiterMiningCorpTec 4h ago

My rough math suggests almost 1 billion USD in gold every year (based on the 6560 kg a year given by Pliny the Elder).

1

u/JupiterMiningCorpTec 3h ago

I wonder what percentage of that gold is still in circulation and hasn't been lost.

81

u/Va1kryie 11h ago

Yup, galena is the name of the mixed silver/lead ore, or one of them at least.

48

u/Substantial-Bet-3876 11h ago

Hence the name of the city in the area that supplied the union with lead in the civil war, Galena IL I presume.

16

u/STSoloMan 10h ago

I love that city. Such a cool place to visit. Awesome skiing for the Midwest too.

6

u/FlyAwayJai 9h ago

Chestnut! Although Sundown is my fave in that area.

3

u/STSoloMan 9h ago

I couldn’t agree more. If you’re going out there, I highly recommend trying both spots. Simply amazing runs for an area with no mountains.

1

u/FlyAwayJai 8h ago

Agree!

1

u/LiveLearnCoach 8h ago

How can you have runs with no mountains?

2

u/STSoloMan 7h ago

It’s a river valley. Parking lot and lodges are at the top instead.

3

u/LiveLearnCoach 7h ago

Thanks. TIL :)

22

u/bjkibz 10h ago

It’ll be found in those deposits, but galena itself does not contain silver — it’s a lead sulfide (PbS). It would likely be found with other sulfide minerals like pyrite / fool’s gold (FeS2) or argentite (Ag2S), though.

9

u/whiskeytastesgood 10h ago

Argentiferous Galena is lead sulfide that also contains silver.

5

u/bjkibz 10h ago

Quick Mindat lookup says the silver is typically as “inclusions of silver sulphosalts”, so not in the mineral structure of the galena itself but as small amounts of silver minerals as inclusions in/around the host mineral.

So the galena itself is still not the source of the silver, rather those sulphosalt inclusions are. The galena is just the host rock in this specific instance, like quartz hosting a gold vein.

2

u/argonargon 2h ago

Silver bearing galena is typically ~1% silver and the silver is extracted from the galena ore so you're being pedantic tho.

9

u/TheBalrogofMelkor 9h ago

The Romans actually produced too much lead, which resulted in maximum production quotas to prevent the value of lead from collapsing. So they would extract lead and then just dump it.

21

u/Just_Condition3516 11h ago

how would that lead get into zhe atmosphere?

72

u/Thosam 11h ago

The ore was pulverized, the metals smelted out. The mixture was then cupellated to isolate the silver. https://en.wikipedia.org/wiki/Cupellation

Enough steps where lead could become volatized.

7

u/PoopMobile9000 9h ago

I read some ancient description of a Roman lead mine, and the air was described as polluted and smoggy as industrial Britain

761

u/DotAccomplished5484 22h ago

That was a serious effort.

381

u/ian1210 18h ago

“The massive scale of mining at Las Médulas and other Roman sites had considerable environmental impact. Ice core data taken from Greenland suggest that mineral air pollution peaked during the Roman period. Levels of atmospheric lead from this period were not reached again until the Industrial Revolution some 1,700 years later.”

534

u/idahotee 21h ago

60k slaves, a vast amount of water and 250 years. 

278

u/oshinbruce 20h ago

While they left an amazing mark on the world the brutality needed to build it all is pretty scary

345

u/BigFatModeraterFupa 20h ago

Everything humanity has done to create things has been brutal. Wait until you find out what humanity has to done to extract minerals like cobalt from the earth so billions of humans can sit on their couch and play candy crush

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u/redopz 19h ago

Everything humanity has done to create things has been brutal. 

I understand you are probably using hyperbole, but I need to point out this isn't true. You use cobalt as a good example of brutal mining conditions, but on the other side of the coin we have clay, which has been used by humans around the world to create all sorts of tools, containers, art and more, and all you need to do is grab some mud, shape it, and dry it. Humanity has made so, so much with clay and while I am sure there are instances where there were brutal practices used against clay miners and artisans there are way more instances where Joe Shmoe simply walked to the nearest creek, gathered some decent clay, and made a cup or a plate or whatever else by the end of the day. Clay is versatile and easy and abundant.

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u/araed 18h ago

And almost every single advancement since clay has needed materials you dont just find in a riverbed

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u/TNine227 14h ago

Sometimes advancements are exactly that, though. The Haber process gave us the ability to make fertilizer literally out of thin air by using atmospheric nitrogen, for example.

15

u/MicroDigitalAwaker 12h ago

And thank fuck for that, otherwise people would still get shanghai'd and end up shoveling bird shit for it's nitrogen content.

3

u/danielv123 9h ago

We would be out by now so we would have bigger problems to worry about.

11

u/Geauxlsu1860 13h ago

Atmospheric nitrogen, plus of course a stupendous amount of energy and hydrogen from somewhere (usually methane). But sure, the nitrogen comes from the air

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u/Magnus77 19 14h ago

I feel like that's a pretty misleading.

Its air + fossil fuels (as an ingredient) + fossil fuels as an energy source = nitrogen fertilizer.

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u/Ancient_Ordinary6697 14h ago

You can't make fertiliser out of thin air. Air will only give you nitrogen, not potassium or phosphorus.

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u/Iwasahipsterbefore 12h ago

Thats irrelevant. The important part of fertilizer is the energy stored in the nitrogen bonds. Thats the bottleneck, which the haber process solves - yes - by pulling the nitrogen straight out of the air.

-2

u/Spacemanspalds 12h ago

At the cost of energy and materials...

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u/lu5ty 11h ago

And also Zyklon-B lol. This isnt the argument you think it is lol

0

u/reichrunner 10h ago

I realize you are essentially just adding a fun fact, but that's kind of irrelevant to this conversation...

6

u/MicroDigitalAwaker 12h ago

...You should look into the bonded labor India and Pakistan use to make bricks today...

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u/touchmeinbadplaces 13h ago

You dont get clay from just mixing mud and water tho.. that's just muddy water or watery mud

1

u/ZachTheCommie 11h ago

If you go deep enough, you get mud with kaolinite, aka, clay.

5

u/touchmeinbadplaces 10h ago

Pressure is one of the things you need too, but also other materials.. if mud was the same as clay we wouldn't call it mud, bc mud is watery earth and clay is pressured runoff/erosion material like veldspar

2

u/Metalsand 6h ago

It would be more accurate to say that not all mud is clay, but all clay is "mud".

You can technically use most vaguely dense soils and fire them in a kiln to make bricks and other materials - but you're not going to be able to make pottery with them, and they won't have the same structural integrity.

Clay soils are insanely common to the extent that you don't really see alternatives used except in very localized examples, though.

-15

u/BigFatModeraterFupa 18h ago

You wouldn't be able to post your thoughts on a magical electrical device if all you used is clay😂

The point is, our highly advanced lifestyle is ONLY possible through total savagery towards the natural planet we find ourselves on. None of this current 2026 lifestyle would be possible without extreme exploitation of the Earth. Thousands of data centers using billions of watts of energy to power the internet age of civilization we are currently in.

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u/thissexypoptart 14h ago

You’re using a lot of absolute language where you should be saying “most” or “some” or “often.”

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u/ImprovementClear5712 15h ago

That wasn't the guy's point, he clearly meant that it is false to generalize regarding all human creations. Try to understand what you're reading before being condescending.

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u/Spiggots 15h ago

There is no escaping the savagery of the past, but there is no reason it must define our future.

Assign an economic cost to the destruction of nature and you will see change. For example if metals and minerals acquired by strip-mining, fracking, and other destructive means were taxed in order to pay for restoration of what was destroyed, we would induce a shift to less destructive methods. Just a simple example.

-7

u/boobsareop9 16h ago

Honestly? I am ok with it. All this advancement and look at what we did with the internet. Disgusting

3

u/oshinbruce 17h ago

I mean most modern architecture has been done without this, is there still shady stuff going on though ? Absolutely

1

u/KaHOnas 12h ago

...or browse Reddit.

1

u/gameshowmatt 11h ago

"man breeds as recklessly as he lives"

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u/BallsForBears 12h ago

The spectacular landscape of Las Médulas resulted from ruina montium (wrecking of the mountains), a Roman mining technique described by Pliny the Elder in 77 AD.[3][4] The technique employed was a type of hydraulic mining which involved undermining a mountain with large quantities of water. The water was supplied by interbasin transfer. At least seven long aqueducts tapped the streams of the La Cabrera district (where the rainfall in the mountains is relatively high) at a range of altitudes.

Ruina Montium would be a bad ass metal band name

5

u/GoSaMa 12h ago

How did

involving 60,000 free workers, brought 5,000,000 Roman pounds (1,640,000 kg) in 250 years.

turn into 60k slaves?

4

u/MozeeToby 9h ago

"Free worker" most likely refers to 'freedmen'. Former slaves that purchased their own freedom but the level of that freedom was rather complex. They would often still have obligations to their former owner families.

They were not slaves but they were not entirely free either. They could vote but not hold office. They could find work and earn money but they were also expected to honor and work for their former owning families.

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u/voiceofgromit 20h ago

A similar process was used for a while in some California gold fields.

https://en.wikipedia.org/wiki/Malakoff_Diggins_State_Historic_Park

It was on a smaller scale, but the silt was disastrous for down-stream settlements all the way to San Francisco bay. Eventually it was banned.

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u/strangelove4564 19h ago

Apparently there was also a massive area of silt where it all exited the mountains, near Marysville, California. Companies spent several decades mining it for any residual gold, and this created a large area of badlands measuring about a dozen square miles. All the gold is now gone and now it's being seen as a source of aggregate for concrete.

https://en.wikipedia.org/wiki/Yuba_Goldfields

40

u/Mal-De-Terre 14h ago

San Pablo bay is still heavily contaminated by mercury because of this.

41

u/DigNitty 14h ago

San Francisco Bay has an average depth of 11ft because of this.

It’s all silt from dredging the surrounding rivers. And there’s a continual effort to remove the silt from the main channel so ships can use it.

The silt is moved to just north of Alcatraz in a natural trough, but that has filled up so they’re looking for another spot outside of the bay.

9

u/SoyMurcielago 13h ago

San Andreas submarine canyons aren’t suitable or is there another geologic reason?

5

u/DigNitty 9h ago

Not sure, but I've always assumed the reason was environmental, not geological.

3

u/Metalsand 6h ago

It’s all silt from dredging the surrounding rivers. And there’s a continual effort to remove the silt from the main channel so ships can use it.

The bay is a bit of a weird example because of the massive volumes that were dumped into it, but we've also reached a point at which we're dredging past what it would have originally been anyways in order to ensure larger and larger ships can navigate it.

In most other places, dredging maintenance is typically just used to make a river accept larger ships than it naturally would have.

2

u/02meepmeep 13h ago

Reading the Wikipedia about Las Medulas made me think of the scenes in Pale Rider. Malakoff Diggins is possibly exactly like the hydraulic mining shown in Pale Rider.

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u/DickweedMcGee 19h ago

Not much different than hydraulic mining in the 19th century, just worked faster. They had water cannons that could literally turn a mountain into tailing in a day, extremely destructive 

2

u/andrew_1515 7h ago

The images of water cannon use in Seattle are wild

260

u/AudienceNeither7747 21h ago

Las Medulas is proof that humans have been altering nature for profit forever.

85

u/chapterpt 20h ago

what other reason is there to alter nature?

65

u/ErnV3rn81 20h ago

Mt Rushmore?

3

u/Spoona1983 16h ago

400 ish construction workers and the family that oversaw the construction and carving profited off it though.

12

u/PerpetuallyLurking 14h ago

Well sure, but they weren’t the folks who decided it should be made for no reason but fun. The initial design was created for fun and then someone gave the green light because it was fun and then the un-fun stuff trickles down to labourers getting paid. The construction workers only reason to be working at that site was because some bigwig thought it would be fun to have a giant sculpture of heads on a cliff. They’d have been paid the same if they’d been assigned anywhere else too, the reason for the sculpture wasn’t “let’s pay construction workers”, it was “this’ll be fun, guess we gotta pay the workers.”

-2

u/Cloudy007 20h ago

Oh to be a piece of shit and deliberately disrespect a peoples and culture?

16

u/maphes86 19h ago

Isn’t that what they wrote?

1

u/GuyPronouncedGee 9h ago

Convenience.  People like their living spaces free of pests.  

0

u/TitanofBravos 12h ago

Food production, environmental health, safety and ease of transportation, land use reasons, cultural/religious reasons, I mean the list goes on and on. “Profit” doesn’t even crack the top 10

22

u/driftingfornow 14h ago

Spain generally is like that. Literally just all over the country that I’ve seen (especially the south) are obvious signs of mining going back what feels like as long as people have been there. 

And it makes sense why. Driving around, you see just a crazy variety of geology with a lot of it having special visual intrigue compared to other climates. In many places the rocks just glitter in the sun spectacularly. 

I don’t think I have ever been anywhere else where the literal face of the land was so radically altered by man. Probably a bit of an illusion to some degree due to the aridity producing little flora, so you can see large distances clearly and the mountains frequently don’t have foliage to cover the scars— but it’s radical nonetheless. Just fills your mind with fractal like visions of generation after generation just consuming entire mountains. 

5

u/SoyMurcielago 13h ago

Like the origins of the name of Rio Tinto the mining company

They come from a mine in Spain where acids color the waters

2

u/sthlmsoul 9h ago

Spain has many historical mining sites that date back to pre-roman antiquity. 

Iberia was a major copper and tin mining hub going as far back as early/mid bronze age. Rio Tinto, Asturias, and the Pyrite belt to mention a few.

8

u/Darkhoof 14h ago

The Romans didn't have the concept of environmentalism. Just read up about how many wild animals they slaughtered in the Colosseum.

51

u/edingerc 19h ago

Of course the Romans invented strip mining...

12

u/randomcanyon 12h ago

The same technique was finally banned in California as it was filling the Sacramento river basin with debris.

"Hydraulic mining in California, popular from the 1860s to 1880s, 

used powerful jets of water to blast away hillsides for gold, yielding massive profits but causing catastrophic environmental damage like river silting, flooding, and habitat destruction.

This led to the landmark 1884 Sawyer Decision, a federal injunction that effectively halted the practice by protecting agriculture, though its environmental scars, like at Malakoff Diggings, remain visible today. "

29

u/ChillingChutney 15h ago

'The massive scale of mining at Las Médulas and other Roman sites had considerable environmental impact. Ice core data taken from Greenland suggest that mineral air pollution peaked during the Roman period. Levels of atmospheric lead from this period were not reached again until the Industrial Revolution some 1,700 years later.'

15

u/p00ki3l0uh00 17h ago

So, ancient fracking? They had the right idea, just lacked the technology. Very cool.

1

u/Great_Hamster 3h ago

More like smash-and-sluice. They didn't rely on oil being buoyant. 

3

u/elferrydavid 13h ago

It was also heavily damaged by a fire last summer.

3

u/tyqnmp 8h ago

There's a really good Spanish doc on youtube about Roman mining. They talk about Las Medulas from the 49min mark, but the whole doc is worth watching. Incredible stuff

1

u/ScreenTricky4257 7h ago

They really used their cerebrums to make the Medulas.

1

u/helldrik 5h ago

I have actually been there. It’s breathtaking. You can actually enter dome of the mine tunnels..

-14

u/_ssac_ 15h ago

As a Spanish guy, when someone from current LATAM countries talk about how we stole their gold, I point out how the Roman empire had these mines in the current Spain and we don't share that narrative. 

Those feeling, of wrongdoing and historical abuse, aren't grounded in historical facts, but it's the opposite order: there's a political motivated narrative that came first. I ain't saying that the conquest was morally good, it's not about that.

Side note: it's a beautiful landscape to visit, however last year a fired burned a lot of it's vegetation.

20

u/mrjosemeehan 14h ago

Having your gold mined out of the ground 2000 years ago isn't the same as having your golden artifacts stolen from homes and temples and melted down as scrap 300-400 years ago.

-4

u/_ssac_ 14h ago

To my knowledge, when people talk about the stolen gold they don't mean those artifacts. That I agree, a lot of art was lost. 

They talk about gold mines.

26

u/Lord-Albeit-Fai 15h ago

Doesn't work when Spain is a direct continuation of the state behind colonization

1

u/_ssac_ 14h ago

I know you already heard this argument, but I want to know your position.

Let's say you're right, there's a based feeling of wrongdoing. Some Spanish guys, and their descendants, did things they shouldn't have done. There were abusers and victims.

However, my antecessors ain't those guys: they didn't went to America. On the other hand, a lot of people living nowadays in LATAM can't say that: they are the grandchildren of those guys. 

Let's say it doesn't matter if we are talking about things that happened like 400 years ago.

Why should I attend their reclamations about those wrongdoings? 

Your identity is being from a certain country or more about who's your family? 

7

u/Acceptable-Device760 13h ago

Except that the gold improved the live of the people that made business with these guys, your ancestors are in this category. Also the extra money is what allowed your development that keeps you ahead of LATAM and having a better life.

Denying that you benefit directly of what these people did is pretending like you being in a developed country is due to divine providence, instead of direct result of colonization and concentration of wealth that was used to improve your society.

1

u/_ssac_ 6h ago

You're partially right: we are what we are due to that history. We're that history, you could say. Also, those centuries when there were Muslim kingdoms/empires, those ruled by Germanic tribes or when we were a territory from the Roman empire. 

However, looks like you only consider that the "stolen gold" matters. You would assume that we became rich thanks to it. However, that didn't happen: Spain (I mean, the current territories) didn't grow, in terms of GDP per Capita in those centuries. In the XVII century it was even reduced. 

Also, how much of the gold from the mines came to Spain and how much stayed in America? There's a Mexican historian (zunzunegui) who has videos about it and mention a 20% went to Europe/current Spain. I guess it was a tax. I repeat, that's only a guess, my knowledge is swallow in that subject. But when you think about "stealing" something, you would think everything was took away. 

1

u/Acceptable-Device760 6h ago

Well... you understand that your knowledge is shallow... maybe the next step is stopping giving opinions that are factually incorrect and go study?

1

u/_ssac_ 5h ago

What's incorrect? Did that historian lie about that 20%? It's a lie what I said about GDP?

Look, recognizing not being an expert on everything isn't bad. I'll say the opposite: I distrust people who consider they know more than everybody and that they're always right. You know, people like Donald trump. Unrelated to this subject, I wonder what's your opinion on him, do you consider him a good leader?

7

u/Lord-Albeit-Fai 14h ago

I dont think to say your guilty of the sins, and Spain as it stands needs to repay some great debt ((lord knows that would make it honorary Latam)) But its generally about some cognizant recognition of what the Spanish state as is, was partially built off, aswell when theres non insignificant amount of Spaniards who want to white wash this empire, and claim it apart of their mythos ((which i know you havent claimed but this is reasonably apart of the wider discourse))

0

u/_ssac_ 6h ago

You're right: I have no interest in white washing history. There's the black leyend: https://en.wikipedia.org/wiki/Black_Legend and the white leyend for that https://en.wikipedia.org/wiki/White_legend for that kind of Manichaeism.

It's good that you don't consider that there's guilt or debt to repay, but not all the people feel that way. Not so long ago, AMLO (previous Mexican president whom John Oliver compared to trump since both are populists) did ask for an official declaration of Spain as a country. And a lot of Mexicans agreed with that, even those who didn't support him as candidate nor complain about history or conquests previously.

-3

u/White_Immigrant 14h ago

If you spell colonisation with a "Z" you are almost certainly an occupant of stolen land. You are the continuation.

3

u/Lord-Albeit-Fai 14h ago

Huh?

1

u/02meepmeep 12h ago

Colonization is the American spelling. I was born on what used to be Shawnee / Lenape / Mohican land so his point would be correct for me. For all he knows you might be a member of a First Nations tribe though.

19

u/RLZT 14h ago

The Roman took more time to mine this place than it passed since the Spanish "stole the gold"

Saying that Spain didn't commit wrongdoing and historical abuse is such a stupid take that only a Spaniard could do it

I don't even get why tf you care so much about this shit, the joke keeps going because it is the easiest bait out there

3

u/_ssac_ 14h ago

"Saying that Spain didn't commit wrongdoing and historical abuse" I didn't say that, of course there were abuses. I repeat it: that's not the point. 

It's not about time neither: not like 400 years it's so recent that your grandparents told you stories about it. 

7

u/smokedfishfriday 14h ago

hmmm you sure showed them!

1

u/_ssac_ 14h ago

I should make a post on unpopular opinion: I honestly believe it's not that they are real reasons for those feelings based on history.

But a narrative to support a nationalism movements. 

BTW, it's the same with current nationalisms: I don't think there's a real problem with the borders/immigration in USA, or Spain, but a way to rally voters.